At this point, this is not about Assad or even Syria, its about fundamental and absolutely crucial principles of international law. It's about telling Uncle Shmuel - NIET! You are not the world's policeman and you cannot force us to submit to your threats.
On one hand, the fact that only Russia and China dared to oppose this resolution (South Africa and Pakistan abstained while Azerbaijan, India, Colombia, Morocco, Togo, Germany, Guatemala, Portugal voted in support) is a pretty good indicator of the relative power of the two sides: Russia and China are still pretty isolated in their opposition to the US Empire. Even India, a fellow BRICS member, did not have the courage to abstain, nevermind oppose, this Resolution. On the other hand, this also shows that Russia and China are powerful enough to act by themselves and that they don't need anybody else's support.
I am not sure that this "¡No pasarán!" will be any more successful than the original one, but it is heartening to see that somebody is still resisting.
No doubt, the anti-Russian hysteria will now reach a new high (for some reason, China's stance is mostly overlooked by the so-called "friends of Syria"), but if that is the price to pay for standing up for what is right, then it is well worth it.